I recently installed a TH400 in my car and the tranny is sitting up higher in the back. Nearly 6 degrees I believe. It even has an Ultrabell which I thought everyone said would hit the trans tunnel and only let you go so far with it. Well not mine, I still have space AND my tranny is angled up in the rear. Am I getting too much angle on my driveshaft and u-joints now? I'm looking at +6 degrees at the tailshaft and -3 on my pinion which makes my driveshaft look like this /

 

is it possible that your bellhousing is not parallel? did you bolt the bell to the engine and use an indicator to check center line run out and the trans surface parallel to the back of your engine? just asked

 

Nope...never did that. Visually it looks great if that matters. Everything seemed to line up perfect.